feat(agent): detect host CPU model and patch ClusterImpNodeProfile at startup

Author: syscod3

internal/agent/cpumodel_linux.go

@@ -0,0 +1,68 @@
+//go:build linux
+
+package agent
+
+import (
+	"context"
+	"os"
+	"strings"
+
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	logf "sigs.k8s.io/controller-runtime/pkg/log"
+
+	impv1alpha1 "github.com/syscode-labs/imp/api/v1alpha1"
+)
+
+// detectAndPatchCPUModel reads /proc/cpuinfo, extracts the CPU model string,
+// and patches it onto the ClusterImpNodeProfile for this node.
+// This is best-effort — errors are logged at V(1) and do not affect agent startup.
+func detectAndPatchCPUModel(ctx context.Context, c client.Client, nodeName string) {
+	log := logf.FromContext(ctx)
+	data, err := os.ReadFile("/proc/cpuinfo")
+	if err != nil {
+		log.V(1).Info("could not read /proc/cpuinfo", "err", err)
+		return
+	}
+	model := parseCPUModelFromProcInfo(string(data))
+	if model == "" {
+		log.V(1).Info("could not parse CPU model from /proc/cpuinfo")
+		return
+	}
+
+	profile := &impv1alpha1.ClusterImpNodeProfile{}
+	err = c.Get(ctx, client.ObjectKey{Name: nodeName}, profile)
+	if apierrors.IsNotFound(err) {
+		log.V(1).Info("no ClusterImpNodeProfile for node, skipping CPU model patch", "node", nodeName)
+		return
+	}
+	if err != nil {
+		log.Error(err, "failed to get ClusterImpNodeProfile for CPU model patch", "node", nodeName)
+		return
+	}
+
+	if profile.Spec.CPUModel == model {
+		return // already up to date
+	}
+
+	base := profile.DeepCopy()
+	profile.Spec.CPUModel = model
+	if err := c.Patch(ctx, profile, client.MergeFrom(base)); err != nil {
+		log.Error(err, "failed to patch CPUModel onto ClusterImpNodeProfile", "node", nodeName)
+		return
+	}
+	log.Info("patched CPU model onto ClusterImpNodeProfile", "node", nodeName, "model", model)
+}
+
+// parseCPUModelFromProcInfo extracts the "model name" line from /proc/cpuinfo content.
+func parseCPUModelFromProcInfo(content string) string {
+	for _, line := range strings.Split(content, "\n") {
+		if strings.HasPrefix(line, "model name") {
+			parts := strings.SplitN(line, ":", 2)
+			if len(parts) == 2 {
+				return strings.TrimSpace(parts[1])
+			}
+		}
+	}
+	return ""
+}

internal/agent/cpumodel_linux_test.go

@@ -0,0 +1,31 @@
+//go:build linux
+
+package agent
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseCPUModel_standard(t *testing.T) {
+	cpuinfo := "processor\t: 0\nvendor_id\t: GenuineIntel\nmodel name\t: Intel(R) Core(TM) i5-8500T CPU @ 2.10GHz\ncpu MHz\t\t: 2100.000\n"
+	model := parseCPUModelFromProcInfo(cpuinfo)
+	assert.Equal(t, "Intel(R) Core(TM) i5-8500T CPU @ 2.10GHz", model)
+}
+
+func TestParseCPUModel_arm64(t *testing.T) {
+	cpuinfo := "processor\t: 0\nFeatures\t: fp asimd\nCPU implementer\t: 0x41\nmodel name\t: ARM Cortex-A72\n"
+	model := parseCPUModelFromProcInfo(cpuinfo)
+	assert.Equal(t, "ARM Cortex-A72", model)
+}
+
+func TestParseCPUModel_missing(t *testing.T) {
+	model := parseCPUModelFromProcInfo("no model name here\nprocessor: 0\n")
+	assert.Equal(t, "", model)
+}
+
+func TestParseCPUModel_empty(t *testing.T) {
+	model := parseCPUModelFromProcInfo("")
+	assert.Equal(t, "", model)
+}

internal/agent/cpumodel_stub.go

@@ -0,0 +1,11 @@
+//go:build !linux
+
+package agent
+
+import (
+	"context"
+
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+func detectAndPatchCPUModel(_ context.Context, _ client.Client, _ string) {} //nolint:unused

internal/agent/reconciler.go

@@ -211,6 +211,9 @@ func (r *ImpVMReconciler) SetupWithManager(mgr ctrl.Manager) error {
 		}
 	}
 
+	// Detect and patch CPU model onto ClusterImpNodeProfile at startup (best-effort).
+	go detectAndPatchCPUModel(context.Background(), r.Client, r.NodeName)
+
 	return ctrl.NewControllerManagedBy(mgr).
 		For(&impdevv1alpha1.ImpVM{}).
 		Named("agent-impvm").